Former Gov. Rick Perry on Wednesday decried a criminal case against him as an attack on his right to free speech and amounted to "the criminalization of politics," one day after a judge ruled that the case could move forward.

"I know my actions were right when faced with a public official's illegal, unethical, and embarrassing public behavior," Perry said, referring to Travis County District Attorney Rosemary Lehmberg's drunk driving arrest in 2013.

Perry, his defense team by his side, spoke to reporters at a downtown Austin hotel following a tour in Iowa and South Carolina in preparation for his likely presidential bid.

On Tuesday, Judge Bert Richardson gave the criminal case against Perry the green light to proceed, rejecting Perry's attorneys' claims that two criminal charges against Texas' longest-serving governor should be tossed because they violated the Texas and U.S. constitutions.

Richardson said that by law, it was premature to consider a constitutional challenge in the pre-trial stage.

On Aug. 15, Perry was indicted on one count of abusing official capacity and one count of illegally coercing a public servant, after the Republican threatened a year earlier to veto funds to the Travis County District Attorney’s office following Lehmberg’s drunken driving arrest.

Lehmberg, a Democrat, refused to step aside, and Perry vetoed $3.7 million to the state’s public integrity unit, which is housed in the Travis County District Attorney’s office.